1. Field of the Invention
The invention relates to a method for laminating a functionalized layered structure to an optical base element with a bi-layer adhesive and the resulting functionalized optical element.
2. The Prior Art
Various films and coatings are combined with optical elements to enhance their performance. Adhesion between polarized films and plastic lenses has been a long standing problem within the industry. The selection of one adhesive always represents a compromise between ease of use, mechanical integrity and optical quality.
One approach is detailed in WO2006/082105 which employs a latex glue in a film transfer process. In EP 1868798 an HMA glue for a film transfer process is described. In WO2007/096521 a polarized film is laminated with a pressure sensitive adhesive. In a mechanical approach described in US2007/0195262, a complex support is used to warp the film during lamination to improve adhesion.
However, the techniques previously disclosed have a number of drawbacks, mainly due to low adhesion or low mechanical performance. Attempts to cure these defects have marginally improved adhesion strength with a loss of optical quality. Accordingly, there is a need to provide a method of adhesive application which compensates for the different material properties of the film and lens surface to provide high adhesive strength in a basic lamination process.